Earlier quoted context omitted.
What you're describing is exactly the opposite of every actually successful team I've seen, and describes every mediocre team I've seen. Silos are death and not just in a code base. Good developers understand the product. Mediocre ones churn out tickets mindlessly.
In my experience, both are needed. Product owners and developers who understand the product. It's possible to have both, they're not mutually exclusive.
Having engineers handle "support calls" doesn't make much sense, they are not equipped to manage product feedback or understand the business implications.